The present invention relates generally to medical devices and in particular to a system of analyzing cardiac data to identify and display groups of cardiac arrhythmic episodes.
Implantable cardiac defibrillators (ICDs) are well established therapeutic devices for treating patients who have experienced one or more documented episodes of hemodynamically significant ventricular tachycardia or ventricular fibrillation. Since their clinical inception more than two decades ago, ICDs have evolved from basic to sophisticated electronic devices that provide physicians with a variety of clinically useful functions with which to treat patients.
Presently, even the most basic of ICDs typically has more than one tachycardia detection criterion, tiered therapy which combines bradycardia support pacing with various antitachycardia pacing modes, low-energy cardioversion, defibrillation, and data logging capabilities. The data logging capabilities within ICDs have become increasingly important, since the amount of data required for the ICDs operation increases proportionally with the increase in ICD functions. Efficiently processing this large amount of data has become possible with the incorporation of microprocessors and memory within the ICD.
Even with the advances in ICD data logging and processing capabilities, arrhythmia event recording capabilities have been limited, making it difficult to verify the adequacy and efficacy of arrhythmia detection and therapy settings. Furthermore, ICDs have been designed to record electrocardiogram and diagnostic channel data which can indicate to the physician the ICDs behavior during multiple tachyarrhythmic episodes. These ICDs also include arrhythmic event counters which log the number of episodes detected and the success or failure of each programmed therapy. Moreover, monitoring capability in some ICDs allow for recording of electrocardiogram waveforms, which can assist the physician in assessing the efficacy of the implanted ICD.
Once an ICD has been implanted, the physician interacts with the ICD through a clinical programmer. The clinical programmer is used to establish a telemetric link with the implanted ICD. The telemetric link allows for instructions to be sent to the electronic circuitry of the ICD and clinical data regarding the occurrence and treatment of a patient""s cardiac arrhythmias and the ICD""s operation to be sent from the electronic circuitry of the ICD to the clinical programmer. The typical programmer is a microprocessor-based unit that has a wand for creating the telemetric link between the implanted ICD and the programmer, and a graphics display screen that presents a patient""s recorded cardiac data and ICD system information to the physician.
As the amount of cardiac data recorded by ICDs increases with each new generation of ICD, manufacturers and clinicians alike are becoming more sensitive to the role that time-efficient programming and data interpretation plays in the physician""s clinical visit with the patient. As ICDs become increasingly complex, the interpretation of recorded arrhythmic episodes and the programming of the ICD can be challenging and time-consuming tasks for some users.
Therefore, a need exists for improved ICD and programmer technology that facilitates the identification of relevant information regarding the patient""s clinical status. There is a need in the art for a system that facilitates the quick identification and presentation of groups of arrhythmic episodes within ICD recorded arrhythmic data.
The present disclosure describes a medical device system for analyzing cardiac data in order to identify and display groups of arrhythmic episodes. In one embodiment, the invention is directed toward a method of receiving the cardiac data representing a plurality of stored arrhythmic episodes, analyzing the cardiac data to identify a subset of stored arrhythmic episodes as a function of user-specified criteria, and displaying the subsets to an interactive screen of a medical device programmer.
According to the invention, only those episodes having characteristics that match the user-specified criteria are displayed. The criteria can be, but is not limited to, an arrhythmia type, a zone of detection, a date of occurrence and an average heart rate in beats per minute (BPM). By analyzing the cardiac data and only displaying the patient""s recorded cardiac arrhythmic episodes of interest, the physician can more quickly assess and interpret the nature of the patient""s cardiac arrhythmias and provide for more effective and efficient programming of the patient""s ICD.
In another embodiment, the medical device system that comprises a cardiac defibrillator and a medical device programmer unit for the cardiac defibrillator. The cardiac defibrillator includes electronic control circuitry for determining and recording the occurrence of arrhythmic episodes of a heart. The programmer unit has programmer electronic circuitry that is coupled to an interactive display screen and which receives cardiac data representing a plurality of stored arrhythmic episodes from the electronic control circuitry. The programmer electronic circuitry analyzes the cardiac data to identify and displays a subset of stored arrhythmic episodes as a function of the user-specified criteria.